South Korea's police are currently investigating a "massive" hack attack on Internet service provider LG Uplus, which led to server outages at three domestic broadcasters and two major banks.

As a result, the army raised its alert status amid concerns the attacks were initiated by its neighbors in North Korea.

Reuters reported Wednesday that authorities were looking into the attack on LG Uplus, which was suspected to be conducted by a group calling itself the "Whois Team".

The investigations were triggered by disrupted servers at television networks YTN, MBC and KBS. Customers at Shinhan Bank reportedly faced problems logging in to their online accounts too, while NongHyup Bank's servers were also affected.